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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /arch/arm/lib/backtrace.S
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'arch/arm/lib/backtrace.S')
-rw-r--r--arch/arm/lib/backtrace.S131
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
new file mode 100644
index 000000000..293a2716b
--- /dev/null
+++ b/arch/arm/lib/backtrace.S
@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/backtrace.S
+ *
+ * Copyright (C) 1995, 1996 Russell King
+ *
+ * 27/03/03 Ian Molton Clean up CONFIG_CPU
+ */
+#include <linux/kern_levels.h>
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+ .text
+
+@ fp is 0 or stack frame
+
+#define frame r4
+#define sv_fp r5
+#define sv_pc r6
+#define mask r7
+#define offset r8
+#define loglvl r9
+
+ENTRY(c_backtrace)
+
+#if !defined(CONFIG_FRAME_POINTER) || !defined(CONFIG_PRINTK)
+ ret lr
+ENDPROC(c_backtrace)
+#else
+ stmfd sp!, {r4 - r9, lr} @ Save an extra register so we have a location...
+ movs frame, r0 @ if frame pointer is zero
+ beq no_frame @ we have no stack frames
+ mov loglvl, r2
+
+ tst r1, #0x10 @ 26 or 32-bit mode?
+ ARM( moveq mask, #0xfc000003 )
+ THUMB( moveq mask, #0xfc000000 )
+ THUMB( orreq mask, #0x03 )
+ movne mask, #0 @ mask for 32-bit
+
+1: stmfd sp!, {pc} @ calculate offset of PC stored
+ ldr r0, [sp], #4 @ by stmfd for this CPU
+ adr r1, 1b
+ sub offset, r0, r1
+
+/*
+ * Stack frame layout:
+ * optionally saved caller registers (r4 - r10)
+ * saved fp
+ * saved sp
+ * saved lr
+ * frame => saved pc
+ * optionally saved arguments (r0 - r3)
+ * saved sp => <next word>
+ *
+ * Functions start with the following code sequence:
+ * mov ip, sp
+ * stmfd sp!, {r0 - r3} (optional)
+ * corrected pc => stmfd sp!, {..., fp, ip, lr, pc}
+ */
+for_each_frame: tst frame, mask @ Check for address exceptions
+ bne no_frame
+
+1001: ldr sv_pc, [frame, #0] @ get saved pc
+1002: ldr sv_fp, [frame, #-12] @ get saved fp
+
+ sub sv_pc, sv_pc, offset @ Correct PC for prefetching
+ bic sv_pc, sv_pc, mask @ mask PC/LR for the mode
+
+1003: ldr r2, [sv_pc, #-4] @ if stmfd sp!, {args} exists,
+ ldr r3, .Ldsi+4 @ adjust saved 'pc' back one
+ teq r3, r2, lsr #11 @ instruction
+ subne r0, sv_pc, #4 @ allow for mov
+ subeq r0, sv_pc, #8 @ allow for mov + stmia
+
+ ldr r1, [frame, #-4] @ get saved lr
+ mov r2, frame
+ bic r1, r1, mask @ mask PC/LR for the mode
+ mov r3, loglvl
+ bl dump_backtrace_entry
+
+ ldr r1, [sv_pc, #-4] @ if stmfd sp!, {args} exists,
+ ldr r3, .Ldsi+4
+ teq r3, r1, lsr #11
+ ldreq r0, [frame, #-8] @ get sp
+ subeq r0, r0, #4 @ point at the last arg
+ mov r2, loglvl
+ bleq dump_backtrace_stm @ dump saved registers
+
+1004: ldr r1, [sv_pc, #0] @ if stmfd sp!, {..., fp, ip, lr, pc}
+ ldr r3, .Ldsi @ instruction exists,
+ teq r3, r1, lsr #11
+ subeq r0, frame, #16
+ mov r2, loglvl
+ bleq dump_backtrace_stm @ dump saved registers
+
+ teq sv_fp, #0 @ zero saved fp means
+ beq no_frame @ no further frames
+
+ cmp sv_fp, frame @ next frame must be
+ mov frame, sv_fp @ above the current frame
+#ifdef CONFIG_IRQSTACKS
+ @
+ @ Kernel stacks may be discontiguous in memory. If the next
+ @ frame is below the previous frame, accept it as long as it
+ @ lives in kernel memory.
+ @
+ cmpls sv_fp, #PAGE_OFFSET
+#endif
+ bhi for_each_frame
+
+1006: adr r0, .Lbad
+ mov r1, loglvl
+ mov r2, frame
+ bl _printk
+no_frame: ldmfd sp!, {r4 - r9, pc}
+ENDPROC(c_backtrace)
+
+ .pushsection __ex_table,"a"
+ .align 3
+ .long 1001b, 1006b
+ .long 1002b, 1006b
+ .long 1003b, 1006b
+ .long 1004b, 1006b
+ .popsection
+
+.Lbad: .asciz "%sBacktrace aborted due to bad frame pointer <%p>\n"
+ .align
+.Ldsi: .word 0xe92dd800 >> 11 @ stmfd sp!, {... fp, ip, lr, pc}
+ .word 0xe92d0000 >> 11 @ stmfd sp!, {}
+
+#endif